Lisp

Lisp
Classification and external resources
Specialty	Pediatrics
ICD-10	F80.8
ICD-9-CM	307.9
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A lisp, also known as sigmatism, is a speech impediment in which a person misarticulates sibilants ([s], [z], [ts], [dz]), ([ʃ], [ʒ], [tʃ], [dʒ]). These misarticulations often result in unclear speech.

Successful treatments have shown that causes are functional rather than physical; most lisps are caused by errors in tongue placement within the mouth. The most frequently discussed of these problems is tongue thrust in which the tongue protrudes beyond the front teeth. This protrusion affects speech as well as swallowing and can lead to lisping. Ankyloglossia or tongue-tie can also be responsible for lisps in children. However it is unclear whether these deficiencies are caused by the tongue-tie itself or the muscle weakness following the correction of the tongue-tie.Overbites and underbites may also contribute to non-lingual lisping. Temporary lisps can be caused by dental work, dental appliances such as dentures or retainers or by swollen or bruised tongues.

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